随后，关于生物航空燃料的严格技术和商务规则被制度了出来，航空公司必须严格遵照执行。

Then there is the long list of exacting technical and commercial specifications aviation biofuels will need to meet.

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虽然欧洲人一般不交换商务礼物，但他们在拜访别的家庭时确实会遵循一些礼仪规则，比如送花。

And while Europeans don't generally exchange business gifts, they do follow some formal customs when visiting homes, such as bringing flowers.

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许多网络公司忘记了一条电子商务的基本规则：网络购物者希望尽可能少的麻烦。

Many web companies forget one cardinal rule of e-commerce: Web shoppers want as little hassle as possible.

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